Comments on: AskPablo: OTEC and Engine Efficiency http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/ Business, Better. Since 2005 Sat, 21 Nov 2009 18:33:24 -0800 http://wordpress.org/?v=2.8.6 hourly 1 By: Guillaume http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14282 Guillaume Sat, 28 Feb 2009 16:08:41 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14282 I've been wondering the same for quite some time, olle holm. I live near the artic (James Bay, actually) and I don't see it being commercially viable but it's a nice dream. One technical problem I see is that the pipe you send under the ice to carry the antifreeze fluid would quickly develop a thick crust of ice all around it because the coolant would be well below 0*C. That's if the ice tension and movement forces don't rip away the pipe in the first place. If someone could overcome all these problems, though, in some remote communities where electricity costs like $0.80/kW*h, there might be potential for part of the year, but it would be too seasonal in most parts... maybe it could be something for the scientists living in Antartica. I guess you could overcome the problem of pipe destruction from ice by passing the pipes through the ground where diving below sea-level, assuming the ground doesn't shift too much. For the problem of ice build-up on the pipes, you could reduce or avoid that by having crazy long pipes that follow the ocean floor very far or something. Not enough consummers at the poles to attract serious attention from the business community, but it could be a niche industry for a wizard of the North of South. Anyways, I saw a cool show on Discovery channel last night about a pump to lift deep ocean water with a buoy oscillating on the waves and a valve at the bottom of the long tube. That reminded me of OTEC and of how the Japanese had difficulty producing net energy because of what it took to lift the deep water with a pump. Because the scientists on the show were hoping to create an artificial ocean bloom to capture carbon dioxide and fight global warming, it was obvious that one revenue stream could be the sell of carbon credit. Along with that and electricty from an OTEC system that works, because on the show the bloom attracted a bunch of small fish and even a whale-shark, another revenue stream could be fisheries, some time of deep-sea fish farm of sorts, an asset in a world running out of fish. Then of course if the process allowed it you could generate and sell clean water to nearby islands and even trace amounts of precious minerals. Sounds like a challenge for me... if only I lived near the tropics. I’ve been wondering the same for quite some time, olle holm. I live near the artic (James Bay, actually) and I don’t see it being commercially viable but it’s a nice dream. One technical problem I see is that the pipe you send under the ice to carry the antifreeze fluid would quickly develop a thick crust of ice all around it because the coolant would be well below 0*C. That’s if the ice tension and movement forces don’t rip away the pipe in the first place. If someone could overcome all these problems, though, in some remote communities where electricity costs like $0.80/kW*h, there might be potential for part of the year, but it would be too seasonal in most parts… maybe it could be something for the scientists living in Antartica. I guess you could overcome the problem of pipe destruction from ice by passing the pipes through the ground where diving below sea-level, assuming the ground doesn’t shift too much. For the problem of ice build-up on the pipes, you could reduce or avoid that by having crazy long pipes that follow the ocean floor very far or something. Not enough consummers at the poles to attract serious attention from the business community, but it could be a niche industry for a wizard of the North of South.
Anyways, I saw a cool show on Discovery channel last night about a pump to lift deep ocean water with a buoy oscillating on the waves and a valve at the bottom of the long tube. That reminded me of OTEC and of how the Japanese had difficulty producing net energy because of what it took to lift the deep water with a pump. Because the scientists on the show were hoping to create an artificial ocean bloom to capture carbon dioxide and fight global warming, it was obvious that one revenue stream could be the sell of carbon credit. Along with that and electricty from an OTEC system that works, because on the show the bloom attracted a bunch of small fish and even a whale-shark, another revenue stream could be fisheries, some time of deep-sea fish farm of sorts, an asset in a world running out of fish. Then of course if the process allowed it you could generate and sell clean water to nearby islands and even trace amounts of precious minerals. Sounds like a challenge for me… if only I lived near the tropics.

]]> By: Anonymous http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14281 Anonymous Wed, 17 Dec 2008 16:56:07 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14281 OTEC is the best form of alternative energy. It doesn't link to any congressional disadvantages. Any negative disadvantage would be outweighed by the OTEC plant built at Diego Garcia. This plan would be perfect to ensure the United State's energy security. OTEC is critical to reduce dependence on foreign oil. We must develop OTEC before the year 2010 in order to avoid the implications of loss of energy dependence, continued reliance on foreign oil, and bickering politics over alternative energies. This plan trades off for the need for environmentally destructive forms of alternative energies such as nuclear power. OTEC is the best form of alternative energy. It doesn’t link to any congressional disadvantages. Any negative disadvantage would be outweighed by the OTEC plant built at Diego Garcia. This plan would be perfect to ensure the United State’s energy security. OTEC is critical to reduce dependence on foreign oil. We must develop OTEC before the year 2010 in order to avoid the implications of loss of energy dependence, continued reliance on foreign oil, and bickering politics over alternative energies. This plan trades off for the need for environmentally destructive forms of alternative energies such as nuclear power.

]]> By: olle holm http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14280 olle holm Mon, 14 May 2007 15:57:10 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14280 Hello, a question about "arctic OTEC": I saw somewhere the idea to utilize the temperature gradient between arctic under-ice seawhater (+1c) and the air above the ice (-40c). Would that be at all feasible for an OTEC-plant? olle Hello, a question about “arctic OTEC”: I saw somewhere the idea to utilize the temperature gradient between arctic under-ice seawhater (+1c) and the air above the ice (-40c). Would that be at all feasible for an OTEC-plant? olle

]]> By: Rick Gandenberger http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14279 Rick Gandenberger Tue, 28 Nov 2006 23:33:44 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14279 Thank you Pablo for bringing up the "efficiency" question. I once worked for a VP of Engineering that insisted solar was far less efficient than Diesel...he designed machines, and didn't pay for fuel. The NELHA example provides a similar situation in connection with OTEC efficiency. NELHA was and is a subscale pilot plant which established that the minimum practical size of an OTEC plant for power production would be 30 MegaWatts. It is interesting that the US Navy, today, is building an OTEC plant at Diego Garcia. The proposed OTEC facility will be designed to provide 7 MW of electrical power and 1.25 million gallons of potable water per day for the island. No threat to the petro-establishment by the Navy! http://resourcescommittee.house.gov/archives/109/testimony/2006/waynearny.pdf On the other hand, NOAA never looked at anything but electrical energy production efficiency. The plant is the second largest exporter in Hawaii, now. Exporting what? Bottled "Deep Ocean" water! Exploiting the varied outputs of an OTEC plant might be very profitable in combination. Distilled water, Oxygen, Nitrogen, Hydrogen, or Ammonia, Methanol. Using cogeneration equipment presently available. At the very least, it could solve potable water problems in small island nations as no other technology can. Please see www.caribotec.com for a few examples. Thank you Pablo for bringing up the “efficiency” question. I once worked for a VP of Engineering that insisted solar was far less efficient than Diesel…he designed machines, and didn’t pay for fuel.
The NELHA example provides a similar situation in connection with OTEC efficiency.
NELHA was and is a subscale pilot plant which established that the minimum practical size of an OTEC plant for power production would be 30 MegaWatts. It is interesting that the US Navy, today, is building an OTEC plant at Diego Garcia. The proposed OTEC facility will be designed to provide 7 MW of electrical power and 1.25 million gallons of potable water per day for the island. No threat to the petro-establishment by the Navy! http://resourcescommittee.house.gov/archives/109/testimony/2006/waynearny.pdf
On the other hand, NOAA never looked at anything but electrical energy production efficiency. The plant is the second largest exporter in Hawaii, now. Exporting what? Bottled “Deep Ocean” water!
Exploiting the varied outputs of an OTEC plant might be very profitable in combination. Distilled water, Oxygen, Nitrogen, Hydrogen, or Ammonia, Methanol. Using cogeneration equipment presently available. At the very least, it could solve potable water problems in small island nations as no other technology can.
Please see http://www.caribotec.com for a few examples.

]]> By: Pablo http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14278 Pablo Tue, 31 Oct 2006 17:50:36 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14278 Thomas, Thank you for bringing this up. Finding uses for what would otherwise be waste is a key part of sustainability. Cogeneration, the generation of electricity and hot water (for heating or domestic use), is a very smart way to maximize the efficiency of fuel use. It seems that you are an authority on OTEC plants. Would you like to share any news or technology updates with us? I am sure that my column left out a few things. Thanks! Thomas, Thank you for bringing this up. Finding uses for what would otherwise be waste is a key part of sustainability. Cogeneration, the generation of electricity and hot water (for heating or domestic use), is a very smart way to maximize the efficiency of fuel use.
It seems that you are an authority on OTEC plants. Would you like to share any news or technology updates with us? I am sure that my column left out a few things. Thanks!

]]> By: Thomas Bjelkeman-Pettersson http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14277 Thomas Bjelkeman-Pettersson Tue, 31 Oct 2006 17:06:39 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14277 <i>So, when a power plant is 35% efficient, 65% of the energy in the fuel become waste (heat, noise, light) and is of no use to us.</i><br /><br /> The 65% you mention is of no use from a electrical generation point of view, but can of course be used to heat housing or other facilities, or can be used for other purposes. To see how that works see:<a href="http://uschpa.admgt.com/CHPbasics.htm" rel="nofollow"> http://uschpa.admgt.com/CHPbasics.htm</a> <br /><br /> In Scandinavia, modern Combined Heat and Power plants can reach as high as 90-95% in their energy use during the winter time. Nearly nothing goes to waste. In hotter climates one can use the waste heat for other purposes, for example to improve the efficiency of a seawater desalination plant. <br /> Best regards <br /> Thomas, Editor at OTEC News, http://www.otecnews.org/ So, when a power plant is 35% efficient, 65% of the energy in the fuel become waste (heat, noise, light) and is of no use to us.

The 65% you mention is of no use from a electrical generation point of view, but can of course be used to heat housing or other facilities, or can be used for other purposes.
To see how that works see: http://uschpa.admgt.com/CHPbasics.htm

In Scandinavia, modern Combined Heat and Power plants can reach as high as 90-95% in their energy use during the winter time. Nearly nothing goes to waste. In hotter climates one can use the waste heat for other purposes, for example to improve the efficiency of a seawater desalination plant.

Best regards

Thomas, Editor at OTEC News, http://www.otecnews.org/

]]> By: Pablo http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14276 Pablo Mon, 30 Oct 2006 20:12:57 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14276 Anything that does not contribute to the intended output is waste/inefficiency. You can have heat from combustion, heat from friction, heat from radiation but you can also have sound from friction, sound from a rapid release of energy (explosion, collision), etc. According to the 1st law of thermodynamics nothing can be created or destroyed. Fuel becomes heat, light, sound, and carbon emissions. Nothing is lost, even though we cannot harness certain "non-product outputs." Anything that does not contribute to the intended output is waste/inefficiency. You can have heat from combustion, heat from friction, heat from radiation but you can also have sound from friction, sound from a rapid release of energy (explosion, collision), etc. According to the 1st law of thermodynamics nothing can be created or destroyed. Fuel becomes heat, light, sound, and carbon emissions. Nothing is lost, even though we cannot harness certain “non-product outputs.”

]]> By: Nick Aster http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14275 Nick Aster Mon, 30 Oct 2006 19:33:29 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14275 Fascinating... so are there no other measurements of inefficiency in the context of mechanics other than heat production? Fascinating… so are there no other measurements of inefficiency in the context of mechanics other than heat production?

]]> By: Pablo http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14274 Pablo Mon, 30 Oct 2006 18:19:44 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14274 Ah, I see... What we are measuring is the efficiency of turning coal (or any other fuel), which has a certain chemical potential energy, into work (turning a turbine), which generates electricity. So, when a power plant is 35% efficient, 65% of the energy in the fuel become waste (heat, noise, light) and is of no use to us. A power plant in the arctic would be more efficient (you can try this out yourself with the Carnot equation) but the efficiency gained would be lost in transmission to a population center. Ah, I see… What we are measuring is the efficiency of turning coal (or any other fuel), which has a certain chemical potential energy, into work (turning a turbine), which generates electricity. So, when a power plant is 35% efficient, 65% of the energy in the fuel become waste (heat, noise, light) and is of no use to us.
A power plant in the arctic would be more efficient (you can try this out yourself with the Carnot equation) but the efficiency gained would be lost in transmission to a population center.

]]> By: Nick Aster http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14273 Nick Aster Mon, 30 Oct 2006 18:13:34 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14273 Sorry got cut off... what I meant to ask it - what exactly are you measureing here? In the coal plant example are you telling me the amount of the coal's potential energy that is getting wasted as heat? How so? The coal has potential energy, it gets burned, it heats water, the water gets really really hot and blasts through a turbine which turns producing electricity. Then the steam get's shot out a smokestack of some kind. So... what are you measureing at the other ened? The coolant water that gets used to chill the spinning turbine? What if you put the coal plant in the arctic with an endless supply of 32 degree water - does this make the burning of coal more efficient in the arctic? How? Sorry got cut off… what I meant to ask it – what exactly are you measureing here? In the coal plant example are you telling me the amount of the coal’s potential energy that is getting wasted as heat? How so? The coal has potential energy, it gets burned, it heats water, the water gets really really hot and blasts through a turbine which turns producing electricity. Then the steam get’s shot out a smokestack of some kind. So… what are you measureing at the other ened? The coolant water that gets used to chill the spinning turbine? What if you put the coal plant in the arctic with an endless supply of 32 degree water – does this make the burning of coal more efficient in the arctic? How?

]]> By: Pablo http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14272 Pablo Mon, 30 Oct 2006 18:11:54 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14272 Nick, The truth is that it does not apply directly to transportation engines since we are talking about electricity generations here. But similar methods can be used to determine the maximum engine efficiency of a vehicle. Our vehicle engines are around 30% efficient. Based on the theoretical maximum efficiency we can't go much higher. The majority of vehicle efficiency improvements are not through engine efficiency improvements. What we can do is to prevent the combustion of fuel when it is not needed (when stopped, going down hill), prevent the loss of energy (aerodynamics, tires, transmission, braking), and teach people to drive more efficiently (by not driving and taking public transit). I think I should save all this fun for another time though... Nick, The truth is that it does not apply directly to transportation engines since we are talking about electricity generations here. But similar methods can be used to determine the maximum engine efficiency of a vehicle. Our vehicle engines are around 30% efficient. Based on the theoretical maximum efficiency we can’t go much higher. The majority of vehicle efficiency improvements are not through engine efficiency improvements. What we can do is to prevent the combustion of fuel when it is not needed (when stopped, going down hill), prevent the loss of energy (aerodynamics, tires, transmission, braking), and teach people to drive more efficiently (by not driving and taking public transit). I think I should save all this fun for another time though…

]]> By: Nick http://www.triplepundit.com/2006/10/askpablo-otec-and-engine-efficiency/comment-page-1/#comment-14271 Nick Mon, 30 Oct 2006 18:03:18 +0000 http://www.triplepundit.com/wordpress/2006/10/askpablo-otec-and-engine-efficiency/#comment-14271 Nice work pablito... can you throw a little more english into this one? Like... how does this apply to planes trains and automobiles? Nice work pablito… can you throw a little more english into this one? Like… how does this apply to planes trains and automobiles?

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